Hand operated single action can opener



May 30, 1967 R. E. M LEAN 3,321,@3@

HAND OPERATED SINGLE ACTION CAN OPENER Filed Dec. 27, 1965 2 Sheets-Sheet 1 29 E y INVENTOR.

4, 9069/? E, Medea/7 W 1967 R. E. M LEAN 3,321.,fi3fl HAND OPERATED SINGLE ACTION CAN OPENER 26 a 61 07b 20a Z 4 if 1 6.5 j 65 l h 53 INVENTOR 2x g; Poerff. Medea/7 United States Patent 3,321,830 HAND OPERATED SINGLE ACTIQN CAN OPENER Robert E. McLean, Raytown, Mo., assignor to Rival Manufacturing Company, a corporation of Missouri Filed Dec. 27, 1965, Ser. No. 516,544 Qlaims. (Cl. -9)

This invention deals generally with can openers and refers more particularly to improvements in the so-called single action type, that is the type wherein all of the operational steps necessary for opening of the can are performed by rotation of a single operating handle.

In my Patent 2,600,792, issued June 17, 1952, there is disclosed a basic single action can opener which utilizes a thrust mechanism for establishing relative movement between two substantially parallel plates. It is this movement between two substantially parallel plates. It is this movement that effects the engagement and piercing of the end of the can by a cutter wheel, and, as subsequently required, releases the opened can from the can opener. One object of the present invention is to provide an increased efiiciency can opener of this general type having a conventional compression coil spring coacting with two parallel plates, e.g., a main support plate and a feed wheel carrying plate, in an unique manner to urge the can feed Wheel toward the overlying cutter wheel whenever a can is engaged in the can opener.

Another object of my invention is to provide a single action can opener which is exceptionally simple and easy to operate as well as having a significantly increased life expectancy. My invention accomplishes the above-mentioned advantages partly through the use of an unique thrust mechanism and an equally unique connecting link located intermediate the coil spring and the can feed wheel. The connecting link is anchored in each plate, thusly confining the pivotal movement of the feed wheel carrying plate to a plane which is parallel to the plane of the link. Accordingly, twisting is substantially eliminated along with adverse friction and wear.

Another highly important object of the invention is to provide, in a can opener having two substantially parallel plates, a means for increasing the efiiciency of operation by providing for a minimum of engagement between the plates while a can is engaged. The resulting freedom of frictional action enables the can feed wheel and the cutter wheel assembly more easily to accommodate the thickened side seam portion of the can head during the cutting relationship. This object is achieved in part by an unique compression coil spring well arrangement. The well is formed in the cooperating parallel plates and so constructed that it allows relative movement of the plates without sliding action between the coil spring and its seat on either plate. A related object is to provide a means for restricting the expansion of the coil spring to a predetermined length. This restriction means facilitates the relative movement of the pltaes and prevents undue distortion of the coil spring.

Other and further objects of the invention together with the features of novelty appurtenant thereto will appear in the course of the following description.

In the accompanying drawings, which form a part of the specification and are to be read in conjunction therewith, and in which like reference numerals indicate like parts in the various views;

FIG. 1 is a side elevational view of a can opener embodying my invention;

FIG. 2 is a fragmentary top plan view of the can opener showing the can feed wheel in the can engaging position;

FIG. 3 is a sectional view taken along the line 3-3 in FIG. 2 in the direction of the arrows;

FIG. 4 is a fragmentary side elevational view of the side opposite the view in FIG. 1 with certain parts broken away to expose portions of the link mechanism, the parts being shown substantially in the positions they assume while a can is engaged in the can opener;

FIG. 5 is an enlarged sectional view taken along the line 55 in FIG. 4 in the direction of the arrows;

FIG. 6 is an enlarged sectional view taken along the line 66 in FIG. 4 in the direction of the arrows;

FIG. 7 is an enlarged sectional view taken along the line 7-7 in FIG. 6;

FIG. 8 is a greatly enlarged sectional view taken along the line 8-8 in FIG. 4 in the direction of the arrows;

FIG. 9 is a fragmentary side elevational view of the frame of the can opener as illustrated in FIG. 3, but with all mechanisms and springs removed;

FIG. 10 is a fragmentary side elevational view of the frame of the can opener as illustrated in FIG. 4 but with wheel assemblies and associated parts removed;

FIG. 11 is an enlarged sectional View taken substantially along the line 11-11 in FIG. 9 in the direction of the arrows;

FIG. 12 is an enlarged sectional View taken substantially along the line 12-12 in FIG. 9 in the direction of the arrows; and

FIG. 13 is an enlarged sectional view taken substantially along the line 13-43 in FIG. 10 in the direction of the arrows.

Referring now to the drawings, and initially to FIGS. 1 through 4, and 8, reference numeral 20 indicates generally an elongate body which comprises the main support structure for the can opener and its operating mechanism. The body, mainly in the form of a vertical plate, may be stamped or otherwise formed of suitable material such as aluminum or steel, and is supplied with the usual looped end 21 through which a hinge pin of a suitable wall mounting bracket may be inserted when installing or mounting the main support structure to the bracket. Through a mechanism later to be described, the can opener is operated by selective rotation of the single operating crank 22 which has a protective cover portion 23 at one end and the swiveled hand knob 24 at the other. Cover portion 23 is rotatable with and secured to crank 22 by the rivet shown at 23a in FIG. 2. The portion of operating crank 22 enclosed by cover 23 is drivingly connected with the serrated or toothed feed wheel 25 located on the left side of the can opener as viewed in FIG. 8. The feed wheel is adapted to cooperate with a cutter member in the form of a cutter wheel 26 in the piercing of a can lid prior to cutting the lid from the can.

Referring now particularly to FIG. 8, the feed wheel 25 is threadedly secured to one end of a feed wheel shaft having four main sections, two of which are the tapered portion 27 and the reduced diameter threaded portion 28 on which the can feed wheel 25 is assembled. As viewed in FIG. 8, the right hand portion of the shaft has the larger diameter section 29 terminating in a square head 30. The square head 3% is of a reduced size and extends through a square hole in the operating crank 22 and is secured thereto by a hot-heading process. A bearing having large diameter ortion 31 with flange 31a and a reduced diameter portion 32 is fitted over the larger diameter portion 29 of the feed wheel shaft with portion 32 engaging portion 29. Shim washer 33 is located between the vertical end of the flanged portion 31a of the bearing and the inside of feed wheel 25 for the purpose of maintaining the outer face of the feed wheel at an optimum spacing relative to cutter wheel 26. The left side of bearing portion 31 is journaled in an opening 36a in plate 36 and has a collar 37 fitted thereover, to the inside of the plate. Plate .36, which will later be described in more detail, is substantially parallel to main support Spacer sleeve 34 and washer 35 are securely fitted over the reduced diameter portion 32 of the bearing and cooperate to properly locate and space operating crank 22 at a correct distance from the frame 20.

The feed wheel shaft and associated bearing 32 and collar 37 are positioned in an enlarged opening 38 in main support 20 (FIGS. 8, 9 and 10), when the can opener is in the can receiving position. As the description proceeds, it is important to bear in mind that all operations of the can opener of the present invention are performed through manipulation of the single operating crank 22. Thus, by appropriately rotating operating crank 22, the feed wheel 25 is moved into and out of cutting relationship with cutter wheel 26. This movement is substantially due to the movement of plate 36, which carries feed wheel 25, relative to the stationary main support 20.

The cutter wheel 26 is rotatably mounted on main support 20 in a manner similar to that disclosed in my Patent 3,165,830, issued Jan. 19, 1965. Main support 20 has an appropriately angled boss 20a formed integrally therewith. The boss is apertured at 20b to allow stud or arbor 39 to be secured thereto, preferably by hot-heading process. Stud 39 has a flange 40 and a reduced diameter threaded portion 41. A combination nut and washer 42 facilitates the assembly and location of cutter wheel 26 on stud 39 for free rotation therewith. As best seen in FIG. 8, the cutter wheel has conical inner face 26a so angled that it substantially parallels the face of the feed wheel where the two confront one another. The cutter wheel 26 also includes the groove 2612 allowing the mechanism to accommodate the can flange in the usual manner.

Located directly below the feed wheel 25 and integrally formed with plate 36 is can guard 43. When the can is engaged in-the cutting position, it is guard 43 that helps properly orient the engaged can for efficient shearing of the end of the can by cutter wheel 26.

Referring more particularly to FIGS. 2 through 4 and 9 and 10, main support plate 20 is appropriately embossed and shaped to cooperate with plate 36 for mounting purposes. For example, embossed portions 44 and 45 assist in maintaining proper alignment of the two substantially parallel plates 20 and 36. Likewise, the rearwardly located embossed portions 46 and 47 further complement the alignment of the two structures. An upper can guide 48 is hot-headed in another boss 48a and projects to engage the top face of the can during operation. An offset trapezoidal shaped cavity or well is formed in the main support plate 20 by the pressed out wall portion 49. The purpose of this will be discussed in more detail later on.

As previously mentioned, operating crank 22 is rotatably connected with the feed wheel shaft at its right hand end as viewed in FIG. 8. Crank 22 includes a portion, designated at 22a in FIGS. 2 and 8, that extends radially past the shaft connection at a suitably selected angle. Crank portion 22a carries a stud or pin '50 which has been hot-headed in place and as such is rotatable with crank 22 about the feed wheel shaft.

Pawl 54 is rotatably connected to main support plate 20. The main support plate has three short projections 51 to which a spacer washer 51a is welded. Washer 51a is centrally apertured to permit the fitting therein of rivet 53. Sleeve 52 is secured in place by rivet 53 after pawl 54 has been mounted thereon. The clinched end of the rivet is received in the opening 51b in plate 20, which the washer 51a overlies. The flanged portion of sleeve 52 and washer 51a serve to locate pawl 54 a prescribed distance from main support 20.

Pawl 54 is provided with an angled terminal portion 54a and a pair of notches 55 and 56. Straight side 57 connects the pair and intermittently acts in cooperation with pin to pivot the pawl for engagement of the pin 4.;- with the respective notches. As seen in FIG. 3, notch is significantly deeper than notch 56 and is generally at a right angle with respect thereto. A relatively light tension spring 58 having one end affixed to main support 20 at hole 58a and its other end to pawl 54 at hole 53b urges the pawl to rotate on its pivot (sleeve 52) in a counterclockwise direction when viewed as in FIG. 3. The counterclockwise rotation is limited by engagement of the end portion 5411 with spacer sleeve 34 surrounding the feed wheel shaft.

As earlier noted, plate 36 is positioned on the opposite side of main plate 20 from hand crank 22 and the feed Wheel shaft and associated members extend through opening 38 in the plate 20. Opening 38 is so sized and plate 36 is so mounted that the bearing 32 and collar 37 surrounding the feed wheel shaft are free to move without interference with support 20 while in any possible operating position.

Plate 36 is designed to carry the feed wheel and thus moves substantially parallel to support 20. A trapezoidal shaped well 59 cooperates with the earlier described reversely shaped trapezoidal well 49 in plate 20 to form a housing for an upright compression coil spring 68. Slightly forward of well 59 is an angled slot 60 through which extends a semitubular rivet 61 which in turn is anchored in an opening 61a in plate 20'. The rivet holds a washer 61b on the exterior of plate 36 so that plate 36 is secured to support 20 but still has sufficient looseness to allow movement of the plate. Rivet 61 has a spacer sleeve 62 telescoped over it to space the plate 36 from plate 20 thus to insure free sliding movement of the plate.

Plate 36 includes a central outwardly offset portion 63. This offset portion partially encloses a pivotal link 64 which aids significantly in the overall operative effects of the coil spring 68, as well as properly aligning the plate and the support. Referring particularly to FIGS. 4 and 5, link 64 is located within offset portion 63 adjacent support 20. The link has holes 65 and 66 into which pins 65a and 66a, respectively, extend. As clearly seen in FIG. 5, pin 65a is anchored in plate 36 while pin 66a is anchored in main support 20. The pins do not extend through the link to engage the plate opposite the anchor point of the pins. Link 64 has a stop surface 64w, which will come in contact with lug 67, the same having been struck from main support 20. The forwardmovement of plate 36 past an optimally aligned position is precluded by the link contacting lug 67.

Returning again to the trapezoidal wells and the compression coil spring 68 located therein, spring 68 is positioned within the rectanguler opening 69 of a captivating plate 70. Opening 69 has a predetermined length calculated to limit the expansion of spring 68. As previously mentioned, both wells 49 and 59 are trapezoidal in shape, however oppositely oriented when the two communicate to form a housing for spring 68. In other words, the narrow end of well 49 is its upper boundary while the narrow end of well 53 is its lower boundary. Spring 63 is positioned within the two communicating wells so that it will seat upwardly in well 49 of main support 20 and downwardly in well 59 of plate 36.

Operation Normally, and as will be seen, upon completion of the operation of opening a can, the crank will be in its said extreme counterclockwise position. The corresponding can feed wheel position is the broken line position as viewed in FIG. 4, that is toward the left and below the solid line position in the same figure. In this position, the teeth of the feed wheel are sufficiently below the cutter wheel as to permit the seating of a can flange on the uppermost part of the feed wheel.

The can is inserted in the position described and held with its top in position to seat upwardly against the edge of the cut-ting wheel as the operating crank 22 is rotated clockwise (as viewed in FIG. 1). As will be seen, upon such initial rotation, the can is lifted against the cutter wheel and forced on up to cause piercing of the can top. Thereafter, continued clockwise turning of the crank serves to advance the can in respect to the cutter wheel as necessary to cut the top completely from the can. It

is not necessary for a user to continue holding the can after approximately the initial one-quarter clockwise rotation of crank 22. After the lid or end has been cut from the can, the user again grasps the can while he rotates crank 22 counterclockwise to the FIG. 1 position, as described above. This in general constitutes the over-all operation of the unit.

During approximately the initial three-eighth clockwise rotation of crank 22 from the open (or FIG. 1) position, pin 50, which rotates with operating crank 22a, leaves notch 55 and travels along straight side 57, raising and pivoting pawl 54 about its pivot 53, until the pin engages in notch 56. At this point, the short portion 22a of the crank and the pawl 54 form an unextended toggle joint with the knee or hinge axis of the toggle at the center of the pin 50. Further clockwise rotation of crank 22 results in straightening of the toggle joint, the accompanying thrust force thereby moving plate 36, including feed wheel 25, from the broken line position seen in FIG. 4, to the solid line position of the same figure. During the aforesaid movement of plate 36, the can feed wheel will en gage under the rim of the can and force the can upwardly, causing penetration of the top of the can by the cutter wheel. When the operating crank reaches the one-quarter clockwise rotation position, feed wheel 25 has moved to its optimum can piercing and cutting position, and further rotation of crank 22 Will be continued until the end of the can is completely sheared from the can. It is seen that each clockwise rotation of the crank (while during the cutting operation) lifts pawl 54 against the resistance of spring 58 whenever pin 50 contacts the terminal portion 54a of the pawl.

After the end has been completely severed from the can, operating crank 22 is then rotated in a counterclockwise direction to disengage the feed wheel and cutter wheel and permit removal of the can (as viewed in FIG. 1). As the crank is rotated counterclockwise, pin 50 enters the squared oil portion of notch 56, raises the pawl and moves out of notch 56 along straight side 57 and into notch 55. With an additional approximately three-eighths counterclockwise rotation of crank 22 after it has formed the toggle with notch 55, the pin 50 fulcrums in notch 55, causing the plate 36 and the feed wheel mechanism to return from the solid line position to the open, or broken line, position, as seen in FIG. 4.

During the time that a can is engaged in the can opener and being cut, the under edge of the rim of the flange of the can seats on the toothed periphery of the feed wheel and the base of groove 26b of the cutter wheel seats downwardly on the rim of the flange of the can at a point spaced rearwardly from the axis of the feed wheel. On the other hand, the can guide 48 seats downwardly on the rim or flange of the can at a point spaced forwardly of the axis of the feed wheel. Can guide 48 is preferably positioned at an elevation relative the feed wheel to maintain the engaged can with its axis rotated slightly counterclockwise from the vertical (when viewed as in FIG. 4). It will be noted that the can guide 48 imparts downward pressure only on the rim or flange of the can and that no part of this can guide bears against the side of the rim or flange of the can.

The projection 43 of the plate 36 maintains the side wall of the engaged can at a predetermined angle (in relation to the adjacent face of the feed wheel) for most efiicient cutting of the end from the can.

The action of the operating crank, associated pin 50, and pawl 54, having been described, it now becomes equally important to consider the movement of plate 36 relative to the stationary main support 20, as well as the forces accompanying the relative movement.

As we have earlier seen in conjunction with FIG. 3,

the engagement of pin 50 in notch 56 and straightening of the toggle linkage causes the movement of plate 36 from a lower rearward position to an upper forward position. The orientation of link 64 relative to plate 36 and main support 20 facilitates this required movement. When plate 36 is in the broken line position seen in FIG. 4, pin 65a will be above and to the left of pin 66a. As the crank arm portion 22a moves pin 50 from notch 55 to notch 56, the seating of pin 56 in notch 56 and further force on crank 22 cause the plate to move. Link 64 is pivotally anchored to support 20 by pin 66a and additionally pivotally anchored to the plate 36 by pin 65a. The straightening of the toggle linkage causes link 64 to pivot on stationary pin 66a. Link 64 rotates in a defined are about pin 66a, thereby swinging pin 65a and the pivotally attached plate 36 upwardly and to the right as viewed in FIG. 4 (or from the broken to the solid line position in the same figure). As the upper terminal end of link 64 moves to the right (as viewed in FIG. 4) eventually stop surface 64a on the link will contact lug 67 whereupon further movement is positively prevented. This forwardmost position has been carefully selected so that optimal cutting action is had by the cooperating feed wheel 25 and the aligned cutter wheel 26 on the can lid. Link 64 is of a relatively short massive construction and by virtue of the fact that it is anchored in both plate 36 and support 20, plate 36 will move only in a plane parallel to that of the link itself. The link construction minimizes any twisting forces and assures the unimpeded free swing of plate 36 during the cutting operation.

The spring 68 serves during can piercing and cutting to provide a resiliently yieldable biasing force tending to pivot plate 36 about the pin 65a in a counterclockwise direction, as viewed in FIG. 4. The condition of the spring after piercing and during cutting is substantially that illustrated in FIGS. 6 and 7. The spring is compressed axially to less than its normal captivated length (controlled by plate 76) between the upper and lower edges respectively of the trapezoidal wells 49 and 59.

The trapezoidal wells 49 and 59 have the effect of cooperating, upon relative movement between plates 36 and 2t), to pivot the spring 68 between the upright position it occupies during piercing and cutting and the inclined position illustrated in broken lines in FIG. 1. With plate 36 in the rearwardmost position (broken line position of FIG. 4) the narrow lower end of well 59 is oifset to the left of the narrow upper end of well 49. In this condition, the spring is inclined to the FIG. 1 position. When in this position, the spring is prevented from exerting force on plate 36 by the spring captivating plate 70 which limits the expansion of the spring to a length less than the distance between the narrow well ends when they are in the relatively offset positions.

When plate 36 moves to the solid line position shown in FIG. 4, well 5h is moved to the right and is also raised. The lateral movement of well 59 relative to the stationary well 49 pivots the lower end of spring 68 to a point where the longitudinal axis of the spring 68 lies in a near vertical plane and the raising of the well compresses the spring.

As mentioned above, spring 68 starts to compress as pin 65a fulcrums in hole 65 of link 64 at about the halfway raised point. Since the feed wheel engages the under edge of the rim or flange of the can, it will likewise move the can upwardly in an obvious manner. The piercing of the can end is actually done prior to the feed wheel reachmg its uppermost raised position and the resulting compression of the coil spring causes the cutter wheel to be driven through the end of the can when the force of the spring is adequate to overcome resistance of the end of the can to penetration by the cutter wheel.

Besides causing cutter wheel 26 to pierce the end of a can, spring 68 maintains the rim or flange of the can in firm but resilient engagement with the toothed periphery of the can feed wheel. This not only assures eflicient traction and feeding of the can by the teeth of the feed wheel but T] allows the can opener to accommodate the thickened side seam portion of a can during the cutting operation.

After the end of the can has been completely severed, crank arm 22 is rotated in a counterclockwise direction (as viewed in FIG. 1) causing pin 50 to seat in notch 55. Further counterclockwise rotation causes link 64 to pivot downwardly and to the left as viewed in FIG. 4 (the broken line position). Collar 37, which surrounds the feed wheel shaft, accordingly moves downwardly with plate 36 and seats in the rearward end of opening 38. This position is sufficient for full can release with respect to the overlying cutter wheel 26 and allows the now opened can to be easily removed from the can opener.

In addition to the advantage usually gained by using single action types of can openers, my invention increases the useable life of the can opener by the use of practically friction-free interconnecting and mating parts such as the unique spring housing. The two substantially parallel plates, plates 36 and support 20, have been mounted with appropriate spacers and embossed portion to make maximum use of the compression spring and as a result an improved, more efiicient can opener can be inexpensively constructed.

It is to be noted that surface 64w of link 64 will always engage the lug 67 as necessary to prevent the collar 37 from ever engaging the forward end of opening 38 of the body 20. Also, action inherent to the design is such that the plate 36 (and all parts mounted thereon) is urged forward (to the right as viewed in FIG. 4) at all times Whenever a can is engaged in the can opener and the feed wheel 25 is rotated counterclockwise (when viewed as in FIG. 4). Inasmuch as the plate 36 is fulcrumed on the link 64 and is unusually free at either end, in respect to the body 20, the spring 68 is not impeded in performing its intended functions. Accordingly, the force of the said coil spring 68 will always cause the rim or flange of the engaged can to be vertically squeezed between the toothed periphery of the can feed wheel 25 and the grooved diameter portion 26b of the overlying cutter wheel 26, for efficient traction, but the plate 36 is exceptionally free to swing on its fulcrum as necessary, against the resistance of the said spring 68, whenever irregularities in the rim of the can are encountered, or the thick side seam portion of the can is passing between the overlapping portions of the feed wheel and cutter wheel. Conversely, it will be apparent that any appreciable friction between the plate 36 and body 2% would interfere with the intended functions of spring 68.

To accommodate manufacturing tolerances, it is preferable that the plate 36, when other parts are in the solid line positions as shown in FIG. 3, be permitted slight additional forward movement (movement to the right as viewed in FIG. 4), before the surface 64a of link 64 engages lug 67 to positively prevent further movement, to assure that the pin 59 will never have interference fit with the notch 5d upon repeated clockwise rotation of the operating crank 22 (as viewed in FIG. 3). Inherent force will automatically cause the plate 36 to move this slight additional amount.

By referring to FIG. 4, it will be seen that the axis of the pin 65a is slightly to the right of the axis of pin 66a. This is to provide a so-called over center position that prevents the plate 36 automatically moving to the left (when viewed as in FIG. 4) upon initial counterclockwise rotation of the operating crank 22 (when viewed as in FIG. 1), before the pin 5% arrives in the notch 55 of the pawl 54. However, it is to be emphasized that, regardless of the position of the plate 36 in respect to the body 20, the operating crank 22 can be rotated either clockwise or counterclockwise for the purposes required without obstruction.

Engagement of the collar 37 with the rearward end of the opening 38 of the body 20 not only prevent further counterclockwise rotation of the operating crank 22 (as viewed in FIG. 1) to indicate to the user that the can has been fully released, but camming action between the said collar 37 and the upper rearward portion of the said opening 38, after the plate 36 has been moved rearwardly approximately to its intermediate position, positively moves the feed wheel 25 to its lowermost position, which amount of separation of the feed wheel from the cutter wheel is required to best facilitate insertation or removal of a can.

From the foregoing it will be seen that this invention is one Well adapted to attain all of the ends and objects hereiuabove set forth together with other advantages which are obvious and which are inherent to the structure.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcornbinations. This is contemplated by and is within the scope of the claims.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter hereinabove set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, 1 claim:

1. In a can opener, the combination of a stationary support plate having an opening defined therein,

a movable plate on one side of said support plate and substantially parallel thereto,

a link member between said plates and pivotally connected respectively thereto on separate axes, said plates each having a well therein, said wells cooperating to form a substantially enclosed space,

a compression coil spring, said spring located within said space and seating on the respective plates at the opposite ends of the wells,

a feed wheel shaft journaled in said movable plate and extending through said opening defined insaid main support plate,

a feed wheel mounted on one end of said shaft,-

a crank arm carrier by said shaft on the opposite side of said plates from said feed wheel,

means cooperating with said crank arm and said link member to effect substantially longitudinal shifting of the movable plate thereby to move the feed wheel shaft between two end positions within said opening in said main support in response to rotation of said crank arm,

a cutter member,

means connecting said cutter member with said main support plate so that in one of said end positions said feed wheel is in can cutting relationship with said cutter member, and

said spring located to yieldably bias said movable plate against displacement thereof in a direction resulting in separation of the feed wheel from the cutter member when said shaft is in said one end position.

2. A can opener as in claim it wherein said wells are trapezoidal in shape, said well in said movable plate hav ing its narrow parallel end adjacent the wide parallel end of the well in said main support plate.

3. A can opener as in claim 2 wherein said spring is pivoted to a non-biasing position upon movement of the feed wheel shaft to the other end position.

4. A can opener as in claim 3 wherein said spring located in said space is a compression coil spring, said spring having associated therewith a means for restricting the expansion of said spring to a predetermined length.

5. A can opener as in claim 4 wherein said expansion restricting means comprises a plate-like member having a rectangular opening defined therein with said spring positioned interiorly thereof, said member located loosely intermediate said movable plate and said support plate.

6. A can opener as in claim ll wherein said link member has two spaced apart pivotal connecting pins located therein, one of said pins connecting said link member to said support plate, the remaining pin connecting said link member to said movable plate, said link pivoted about a fixed axis on said first mentioned pin, said second mentioned pin journaled within said movable plate and operable to move with said movable plate relative to said support in response to rotation of said crank arm.

7. A can opener as in claim 6, said link having a stop surface on its terminal end opposite said first mentioned pin, said main support plate including a stop lug, said pivotal movement of said link being limited by the engagement of said stop surface with said stop lug, and accordingly limiting the feed wheel to a preselected position when in cutting relationship with said cutter memher.

8. A can opener as in claim 1 wherein said movable plate is mounted for pivotal movement relative to said support plate, said coil spring positioned relative to said plate and said main support to resiliently urge said movable plate about its pivot axis and feed wheel towards said cutter member when the latter is tion.

in the can cutting posi- 20 9. A can opener as in claim 1 wherein said shifting means includes a pivoted pawl spring biased toward said feed wheel shaft, said pawl having a first and second notch defined therein, the first notch providing a seat for a portion of said crank arm, said seat acting as a fulcrum point for moving said movable plate and forcing said feed wheel shaft toward said cutter member.

10. A can opener as in claim 9 wherein said second notch provides a seat for said portion of said crank arm, said seat acting as a fulcrum point for forcing said movable plate and feed wheel shaft away from said cutter member.

References Cited UNITED STATES PATENTS 6/1953 McLean 30-9 11/1954 Talge et a1. 309 

1. IN A CAN OPENER, THE COMBINATION OF A STATIONARY SUPPORT PLATE HAVING AN OPENING DEFINED THEREIN, A MOVABLE PLATE ON ONE SIDE OF SAID SUPPORT PLATE AND SUBSTANTIALLY PARALLEL THERETO, A LINK MEMBER BETWEEN SAID PLATES AND PIVOTALLY CONNECTED RESPECTIVELY THERETO ON SEPARATE AXES, SAID PLATES EACH HAVING A WELL THEREIN, SAID WELLS COOPERATING TO FORM A SUBSTANIALLY ENCLOSED SPACE, A COMPRESSION COIL SPRING, AND LOCATED WITHIN SAID SPACE AND SEATING ON THE RESPECTIVE PLATES AT THE OPPOSITE ENDS OF THE WELLS, A FEED WHEEL SHAFT JOURNALED IN SAID MOVABLE PLATE AND EXTENDING THROUGH SAID OPENING DEFINED IN SAID MAIN SUPPORT PLATE, A FEED WHEEL MOUNTED ON ONE END OF SHAFT, A CRANK ARM CARRIER BY SAID SHAFT ON THE OPPOSITE SIDE OF SAID PLATES FROM SAID WHEEL, MEANS COOPERATING WITH SAID CRANK ARM AND SAID LINK 